Problem 682. Image Processing 002 : Fix Vignetting in a Visible Sensor

Created by Richard Zapor

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The task is to correct image files for Visible scanning sensors that due to errant tolerancing produce vignetted(V) images. The V artifact is in a converging ray bundle and only the edges are impacted to differing amounts. The obscuration varies cross-scan but is constant for all samples. Sensor package repair is cost prohibitive. Luckily, the Image Processing is Matlab based and needs only a fast function to perform the V adjustment good enough for govt work.Output: Fixed image(Fimg) (Array &lt;= 512x512 of type double)Input: Vignetted Image file(Vimg) (double); Obscuration (1xncol)Tolerance: Good enough is 1%+1 count of Truth (Timg)Obscuration: Max is 25% at edge, Min 8 columns wide.Vignetted Image creation: Start with Truth (Timg)Vimg = Timg(1-Obscuration)example: Obs = [.25 .1 0...0 .1 .25]; obs [50 20 0...0 20 50];load penny.mat; Timg=double(P);Vimg=Timg.*repmat(1-Obs,128,1)The Cody "Image processing 001" for an IR and using In-scene data was not intended to be so complex. This and its successor should have appeared prior to "001".This Visible Vignetting correction is very direct.

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Problem 682. Image Processing 002 : Fix Vignetting in a Visible Sensor

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Problem 682. Image Processing 002 : Fix Vignetting in a Visible Sensor

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